Hydraulic punching



Feb. 11, 11. T. c. RIGDON HYDRAULIC PUNCHING 3 Sheets-Sheet 1 Filed April 15, 1940 Feb. 11, 1941. C RlGDON HYDRAULIC PUNCHING Filed April 15, 1940 3 Sheets-Sheet 2 J v QQ 3mm madam Thumna E Elam/M44 Feb. 11, 1941. c, D N 2,231,638

HYDRAULIC PUNCHING Filed April 15, 1940 I 3 Sheets-Sheet 3 I I 74? Thumui [.PWUUTL Patented Feb. 11, 1941 UNITED STATES TENT OFFICE 3 Claims.

This invention relates to accurate control of reciprocable elements, especially in a cutting or dressing tool.

This invention has utility when incorporated in fluid operable punches, more particularly of the fixed piston and movable cylinder type.

Referring to the drawings:

Fig. l is a side elevation, with parts broken away, of an embodiment of the invention for a group of the tools adapted to Work upon a common part as the cowl portion of an automobile;

Fig. 2 is a View of the tool unit, more particularly as developed into a readily portable pistol or gun type of device;

Fig. 3 is a section on the line IIIIII, Fig. 2, showing features of the end of the movable operating cylinder;

Fig. 4 is a section on the line IVIV, Fig. 3, showing the assembly between the cylinder and piston;

Fig. 5 is a section on the line VV, Fig. 4, showing a fluid connection to the tubular piston rod;

Fig. 6 is a section on the line VI- -VI, Fig. 4,

' showing the movable cylinder after portion as mounted on the tubular cylinder rod or stem;

Fig. 7 is a View of an accessory beyond the showing of the device of Fig. 4, wherein there may be a locating or positioning of the gripping means in a determined sequence from theother relatively movable parts, herein shown by means of a spring response;

Fig. 8 is a fragmentary view, wherein this control is by independent power means, herein shown as a solenoid; and

Fig. 9 is an additional form of this supplemental action, wherein the release may be by normal transit from gravity.

Main frame I may have seat 2 in forming a fixed die, upon which may be placed work 3, say sheet metal which may be preferably configured to approximate the contour of a cowl of an automobile. As so placed, the units of the invention herein may act thereon simultaneously or, if preferred, in sequence; this action to be for definite location or development toward a finished product in which the holes for assembly or mounting are accurately located herein by punching.

With this purpose in mind, on the frame I there may be located a base 4 for the respective units, such being definite anchorage in the desired location as to direction and spacing relatively to opposing die portion 2. In this set-up there is power head or fitting block 5, from which extends duct 6 to branch line 1. Additionally,

nection with the assembly herein, with the fixing 5 of the bases l, these ducts 1, 10, are rigid passages and will retain the fluid pressure in this hydraulic power source device, wherein, for a socalled hydro-power unit, eccentricity of a ring may control the functioning of motor driven shaft l2, eiTective at central position as a neutral and thereby causing flow in neither the line H) nor the duct 1. Shifting of this eccentric is effected in glands or packing [3 by rod means Hi.

In the set-up herein, lever I5 having rockable fulcrum I6 is operated from a source by link ll, angle lever I8, link l9, and arm from handle 2! having fulcrum 22 on the frame I. Accordingly, the operator for the hand lever 2| may locate the eccentric by the placing of this reciprocable means l4 so that flow of power fluid may be by way of the duct 9 and fitting 8 into the block 5 and thus provide power fluid flow within the tubular piston rod or stem 23 (Fig. 4) for flow from thence by way of lateral ports 24 into cylinder 25, thereby causing cylinder head 26 to be shifted toward the block 5 and locating piston 21 adjacent cylinder head 28. In this reciprocating movement of the cylinder 25, such cylinder has longitudinally thereof guides or ribs 29 (Fig. 6) adapted to work in ways of directing block portion 30, strips 3|, and holding strips 32 as anchored therewith by screws 33. Gibs or guides in the desired overhang, whether straight and beveled and gibbed, interlocked, .or dovetailed, are efiective for definite accurate guiding, desirably for the full length of travel of this cylinder in the functioning hereunder. This is a definite means for accuracy in control against vibration disturbance even in heavy impacting operations and is thereby a feature for maintained accuracy in the cutting tools.

The reverse shifting of this hand lever 2| to the neutral or idle position merely holds this cylinder at the withdrawn position. Further shifting past this neutral or idle position for the power fluid delivery by way of the duct 5 at the block 5, thereby delivers power fluid to the inner, central or concentric stem or tubular piston rod 34 having tubular delivery port 35 adjacent the cylinder head 28, thereby to cause the cylinder head 26 to travel along the concentric piston rod away from the block 5.

In the construction hereunder, this cylinder head 28 has assembled thereon by screws 36 tool carrier block 31. This block 31 has openings 38 therein, through which screws 39 extend for threaded connection with stripper plate 40. Heads 4| of these screws 39 may retract in clearance 42 of this block 31 toward the cylinder head 28. However, in normal functioning, compression helical springs 43 thrust this stripper plate 40 away from the block 37. The stripper plate 46 has port 44, herein shown as centrally of this stripper plate 46 and as a single guide. However, there may be variation as desired for tool 45, herein shown as a punch, rigid with holder 46 therefor mounted in the block 31. This means that as work 41, against die 46 having complementary opening 49 as to the punch 45, is located definitely with this hydraulic piston and cylinder device, and as herein adapted to holding frame 30, such may be a portable device by pistol grip 56 as a directing means therefor. This base 36 thus positively and rigidly locates the die 48.

In this functioning of the power stroke from the fixed piston 21, the movable cylinder has its head 28 moved toward the anvil or die 43. Stripper plate 49 first contacts the work 47 to place the work against the die 48'and. hold such work as the tool 45 thereafter enters and punches this article of work 4? and further proceeds into the complementary die port 49. As the stroke is completed, and there is reversal of operations from the control, such as first to neutral in holding the piston and cylinder relatively to each other; then as back the return flow is permitted by way of the duct or central tubular piston 34, while power fluid is supplied into the outer tubular piston 23, surrounding this tubular piston 34 and thus this power fluid is delivered in the cylinder 25 between the piston 2'! and the head 26. There is thus a retracting movement first effecting a stripping of this tool 45 from the work 4'! as the stripper plate 45 initially holds the work. As this tool is cleared of the work, the stripper plate is then retracted and the work 41 is clear for removal and replacement for repetition of this cycle of operations. The tubular piston rods herein are shown as concentric. However, in the working up of the tool the provision herein is for an intake and outlet duct for the cylinder, preferably against travel with the cylinder, and this is thus effective through the tubular means as mounting the piston and directing such as the cylinder is guided in its movement relatively to the piston.

The directed block portion 29, instead of being carried by the block portion 30 may be mounted I on supplemental block portion (Fig. 7) as a directing guide having slide guide 52 in fixed base 53. Fixed with this directing block 5| is laterally extending bracket portion 54 having slidably mounted therein bolt 55 having head 56. This bolt 55 has thread engagement 51 with the fixed base 53 and helical compression spring 58 normally holding this auxiliary block guide 5| spaced from the base 53. This spring 58 may be of different compression response than the spring 43. Accordingly, in the action of the. cylinder 25 and the piston therein, movement may be to stop 59 fixedwi'th the base 53, and, as the pressure further builds up therein, complementary work face 59 may approach work 6| as against traveling face 52 and thus eifect gripping of the work. This functioning may, as herein disclosed, be effected through the shifting of the directing block 5| as to the base 53 and against the resistance of the spring 58. In this transit, the complementary portion 56 is brought into nesting relation as to the parts 62 in holding the work 6| therebetween. The springs 43 come into play for the response yielding gripping action in this stage. The utility hereunder arises that in the reverse or release of the work hereunder, the transit-effecting guide 5| permits shifting of the form 6|] away from the gripping relation as to the work to a greater degree than merely stripping the working tool or punch from the work. Accordingly, such tool as effecting cutting, punching, shaping, or other operation, has the work not only released therefrom but cleared from the work so that the work may be readily placed and removed. In the operation of the device (Fig. 7) fixed stop 59 is abutted by stop 63 fixed with the cylinder 25 to determine the limit position,

In the device (Fig. 8), in lieu of the fixed stop 63, there is provided stop 64 having adjustable mounting 65 which, as coming into position with the fixed stop 59, may thus determine the location position for the cylinder 25 as to work 66. This means taking care of different dimensions of work as between form 6'! with the cylinder 25 and form 68 as the gripping means control. Additionally, instead of the helical spring 55, there may be stem 69 fixed with bracket 19 on the movable directing block 5|. This stem 69 has plunger H in coil 12 to act as an electromagnet which may have its control supplementally energized by the functioning of push switch [3 from stem 14 fixed with the bracket 16.

This feature of Figs. 7, 8, as well as Fig. 9, is a featiue for clearance in release of work. Fixed portion 75 (Fig. 9) has bolt 16 in adjustable engagement therewith and loose in its connection with bracket Ti fixed with the auxiliary directing guide 5| slidable as to the base '15. Herein, as the cylinder 25 operates to bring form 18 toward form '79 to engage work 86 therebetween, there is gripping means response through the springs 43 effective to strip the tool. As such stripping is effected, the positioning, as for the cylinder 25 to withdraw, allows gravity to hold the parts including the member i9 against tendency to follow the cylinder 25 in its retracting and thus frees the work 86 more readily from the tool operation herein.

What is claimed and it is desired to secure by United States Letters Patent is:

1. A piston, duct-providing rigid means to and from the opposite sides of the piston, a cylinder for the piston, a guide for the cylinder, a tool fixed with the cylinder, work gripping means, a spring device for maintaining the work gripping means normally in advance of the tool, adapted to be retracted upon engagement of the work to expose the tool for acting upon the work and further to hold the work in retraction of the tool clear of the work and thereby serve as a stripper for the tool as to the work prior to release of the work by the device, and a fluid supply control effective through the duct means to oppose the spring device in one direction and supplement cylinder travel away from the spring device in the opposite direction.

2. In a power tool, a fixed support, a piston, a cylinder for the piston, motive fluid connections to the opposite sides of the piston in the cylinder, guide means for directing the cylinder shifting as to the piston, a stop fixed with the support, a first member shiftable with the cylinder toward work-engaging position to abut the stop, additional guide means, and a second workengaging complementary member yieldably carried by the additional guide means and actuable from the piston for bringing the second member into Work gripping position as to the first member, and complementary tools fixed with the respective members for acting upon the gripped work and relatively to one of the members.

3. In a power tool, a support, a cylinder, a first guide mounting for the cylinder, a piston for the cylinder, a second guide mounting for the piston and directing the first guide mounting, a stop fixed with the support, a first work gripping member shiftable by the first guide mounting to abut the stop, a second complementary Work gripping member shiftable by the second guide mounting toward the first member to efiect gripping of work therebetween, yieldable mounting means for the second member as to the second guide mounting, a tool fixed with the second guide mounting, and operating means for the piston and cylinder and mountings to effect functioning of the tool following the gripping of the Work in one direction of piston and cylinder operation and for withdrawing the tool clear of the work in stripping the tool from the Work and thereafter releasing the work in the reverse direction of the tool operation,

THOMAS C. RIGDON. 

